Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 |
XNAV Steer Your Way By X-Ray Pulsar
XNAV - or X-ray Navigation - could be the GPS of the solar system (or even the galaxy). X-ray astronomers have mapped a substantial number of x-ray pulsars whose pulsed emissions are as regular as atomic clocks. Several papers will be presented at the IEE/ION PLANS 2008 conference describing how this idea could be applied for spacecraft navigation.
An X-ray pulsar is a magnetized neutron star in a binary star system with a normal companion star. The strength of the magnetic field of a neutron star is a trillion times as large as the Earth's magnetic field strength measured on the Earth's surface.
(X-ray pulsarx-ray pulsar)
Material from the companion star is taken in by the neutron companion, directed into the magnetic poles. This gas falls into the neutron star at speeds of up to half the speed of light; the resulting hotspots generate temperatures of more than a million degrees. As the neutron star rotates, these polar hotspots produce regular pulses of x-ray radiation like lighthouses.
These sources are highly reliable, and are fixed in position. Phase measurements of these sources can be used to establish the location of a spacecraft.
Several different improvements to the use of X-ray Navigation have been proposed. In Noise Analysis for X-ray Navigation Systems, it is suggested that the performance of an XNAV system beyond the orbit of Jupiter could be accurately predicted.
In Online Time Delay Estimation of Pulsar Signals for Relative Navigation using Adaptive Filters it is suggested that the positions of two spacecraft could be determined if both are locked to a known pulsar which emits a waveform that reaches them with a differential time delay that is proportional to the distance between the spacecrafts. The spacecrafts' relative inertial position could be determined by observing appropriately distributed pulsar sources.
Astronomers have thought long thought about pulsars, which were discovered in 1967, as some kind of interstellar beacon. The incredible regularity - and rapidity - of the signal pulsation seemed (at that time) to have no natural explanation.
However, science fiction writers thought about it at least fifteen years earlier. And what's more, suggested that it might be possible to create beacons. In his 1952 story Troubled Star, George O. Smith wrote about space beacons which were created to ease galactic space travel:
"We use the three-day variable to denote the galactic travel lanes. Very effective. We use the longer variable types for other things - dangerous places like cloud-drifts, or a dead sun that might be as deadly to a spacecraft as a shoal is to a seagoing vessel. It's all very logical.""...you're going to make a variable star out of Sol, just for this?"
Scyth Radnor shook his head. "Please do not think us hard... You're not going to insist that your animal comforts are more important than the functioning of a galaxy-wide civilization?"
(Read more about space beacons)
From IEE/ION PLANS 2008 via io9.
Scroll down for more stories in the same category. (Story submitted 5/8/2008)
Follow this kind of news @Technovelgy.| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
Would
you like to contribute a story tip?
It's easy:
Get the URL of the story, and the related sf author, and add
it here.
Comment/Join discussion ( 1 )
Related News Stories - (" Space Tech ")
Lava Tubes On Moon And Mars
'...it never was built, or anything like that; it's just a big volcanic bubble.' - Robert Heinlein, 1957.
SpaceX EVA Spacesuit Tested By Polaris Dawn Crew
'Now, except for weight and heat, the same conditions prevail in this chamber as in space.' - Otto Willi Gail, 1929.
ESA To Build Moon Bases Brick By Printed LEGO Brick
'We made a crude , small cell and were delighted - and, I admit, somewhat surprised - to find it worked.' - John W. Campbell, 1950.
FLOAT Levitating Train On The Moon ala Clarke
'The low-slung monorail car, straddling its single track, bored through the shadows on a slowly rising course.' - Arthur C. Clarke, 1955.
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
Current News
Biohybrid Robots Made Of Living And Synthetic Materials
'If the biological robots were not living creatures, they were certainly very good imitations.'
Drug Induces Hibernation-Like State In Humans
'... drugged and chilled and stowed in sleep tanks.'
Poul Anderson's 'Brain Wave'
"Everybody and his dog, it seemed, wanted to live out in the country; transportation and communication were no longer isolating factors."
AI Note-Taking From Google Meet
'... the new typewriter that could be talked to, and which transposed the spoken sound into typed words.'
Qore IcePlates Are Personal Cooling Suits
'... underneath they consisted of networks of cooling tubes against the skin.'
P1 Just The Latest Robot To Take A Beating From Humans
'...we mere people come second.'
Waymo Cars Shout At Each Other, Autonomously
'My cars talk to one another. I have no doubt about it...'
Your Solar Electric Paint Is Ready, Larry Niven
'...you spray it on.'
How Long Till We Have These Tattoos?
Truth or fiction?
Seeing Faces On Grains Of Sand (AI Pareidolia)
'... the imprint of her image on the telephoto cell.'
Lunar Biorepository Proposed For Cryo-Preservation Of Earth Species
'...there was no one alive who had ever seen them. But they existed in the Life Bank.'
Tele-Driving Offers Jobs For Tele-Drivers, Not AIs
''...some bored drone pusher in a remote driving centre...'
Autonomous Robotic Dentist - Would You Say 'Ahhh'?
You might be surprised at how much more efficient this could be.
GM Scraps Cruise Origin Robotaxi With No Steering Wheel
'Ames tinkered around with something on the instrument board when he got in; and in a few moments we were off.'
Taza Aya Air-Curtain Tech Protects Turkey Workers
'I'm going to have to buy a filter-mask.'
Torobo Humanoid Robot Hammers A Nail
7-axis dual arms, 3-axis waist (pitch, pitch, yaw), 3-axis neck (yaw, pitch, roll), and 4-axis undercarriage!
